Crash Course: Video Camera Lenses
When you buy a video camera, there’s a lot to agonize over. Brands. Type of camera. Type of sensor. Generation. The decision-making process is made worse if you don’t fully understand cameras and you’re not sure where to start. There’s so much to consider, and all the information that’s thrown at you during the process can make for a daunting series of choices.
No matter what, remember this: if you have a video camera, the lens plays one of the most vital roles in taking high quality video. It’s also extremely important to choose a lens that’s appropriate for what you’re shooting.
Video cameras and fancy lenses aren’t for everyone
First things first: most phone cameras nowadays can shoot video that works just fine for basic content, but if you’re looking for something that takes it to the next level (quality-wise), you might want to start looking at more professional options.
Here at Looma, we use several different types of cameras, chief among them being the Sony FX3, which is a versatile, relatively inexpensive consumer-grade camera that shoots 4K video and works well in in a range of light conditions. The FX3 is extremely adaptable and can shoot just about anything — ranging from small social media videos to literal Hollywood action movies. We also often use a DJI Ronin, which is great for shots with lots of movement thanks to the built in stabilizing gimbal as well as it’s capacity to be controlled remotely)
The Sony FX3 is a versatile consumer-grade camera with excellent performance in a variety of different lighting conditions.
As far as lenses go, however, we have many, many different ones to choose from – depending on what we’re shooting, where we’re shooting, how we’re shooting, and when we’re shooting. When we’re filming athletics or events, for example, we use a lens with quick autofocus and a lot of zoom. For interviews, we’re likely to use prime 35mm lenses for their wide aperture, which allows lots of light and blurs the background nicely.
As you can see, there’s a lot of terminology and camera jargon that can make buying your first lens intimidating. This guide will walk you through essential lens terms like zoom, focal length, prime, aperture, depth of field, lens mounts, manual focus, and auto-focus, as well as the importance of choosing the right lens for your camera – and your subject.
Zoom: Getting Closer to Your Subject
Zoom lenses offer varying focal lengths, allowing you to zoom in and out without changing lenses. They are versatile and ideal for situations where you need flexibility, such as athletics, candid shoots, event coverage, and even landscapes (capturing a wide shot of a landscape and then zooming in on a specific subject, for example).
There are two types of zoom lenses:
Optical Zoom: Adjusts the lens elements to magnify the image before it reaches the sensor, preserving image quality.
Digital Zoom: Crops and enlarges the image using software, often resulting in a loss of quality.
For the best results, always prioritize optical zoom.
Crash Course: Focal Length
Though there’s a little more to it if you’re willing to do a deep dive, focal lengths are generally quite simple: the higher the number, the more zoomed in you are. Focal lengths can often be as low as 8mm (for an extreme fisheye) and as high as a ludicrous1200mm.
A more typical focal length between 16mm and 35mm, for example, is considered a wide angle and will set the viewer far away from your subject. A wide angle allows you to fit a lot into your frame and would be ideal for something like a landscape shot or a real estate listing/virtual tour where you need to fit a lot of visual information into one shot without necessarily choosing a specific subject.
A longer focal length – let’s say 135mm or more – zooms you in close to your subject. You can fit less in the frame, but it allows you to get closer to your subject without literally getting closer. A longer focal length would be ideal for filming sports, events, weddings, and wildlife. Remember, though: if you’re shooting handheld, a longer focal length requires a steadier hand.
Prime Lenses
A prime lens is a lens that operates at a fixed focal length. In other words, it’s a lens that doesn’t zoom. Though they may be a little less versatile, a prime lens often boasts a lower aperture (see below), which means they’re better for low light and a narrower depth of field. They’re well suited for videographers who know exactly what they’re shooting and often work well for stationary shots with a clear subject (such as interviews) and low-light filming.
Aperture: Controlling Light and Depth of Field
Aperture can be a little confusing because it controls two things: light (exposure) and depth of field. It’s measured in f-stops (e.g., f/2.8, f/4, f/5.6).
Zoom lenses generally have a lower aperture (higher f-stop number), which makes them somewhat less suitable for low light; moreover, the aperture of inexpensive zoom lenses often changes as you zoom in or out, meaning the exposure (brightness) of your video will change in real time. If you’re buying a zoom lens, spring for one with a consistent, larger aperture (like 2.8).
The aperture size impacts two critical aspects of your footage:
Light. As we already stated above, a larger aperture (lower f-stop number) lets in more light, which is beneficial in low-light conditions.
Depth of Field. A larger aperture also creates a shallow depth of field, which makes your subject stand out against a blurred background. Conversely, a smaller aperture (higher f-stop number) results in a greater depth of field, keeping more of the entire scene in focus. Next time you watch a movie, look carefully at the backgrounds of given shots — especially closeups —and take note of whether or not they’re blurred. If they are, a lower aperture was used.
Illustrating depth of field (Source: Photography Life)
A still shot from on of our video business cards. As you can see, the background is quite blurred and, despite the low light of the room, the subject is of the shot is plainly and sharply visible.
Lens Mounts: Connecting Lenses to Cameras
The lens mount is the physical interface that connects a lens to a camera body. Different camera manufacturers use various mounts, so it’s essential to ensure compatibility between your lens and camera. Some common mounts include:
Canon EF/EF-S: Widely used in Canon DSLR and mirrorless cameras.
Nikon F: Common in Nikon DSLR cameras.
Sony E: Found in Sony mirrorless cameras.
Micro Four Thirds (MFT): Used by Panasonic and Olympus.
Adapters are available to use lenses across different mounts, but they may affect the functionality of things like auto-focus and image stabilization.
Manual Focus vs. Auto-Focus: Precision vs. Convenience
Manual Focus: This mode allows you to adjust the focus ring on the lens manually, giving you complete control over what’s in focus. It’s invaluable for situations where auto-focus might struggle, such as low light, scenes where your subject is moving quickly (such as sports), or scenes with multiple subjects.
Auto-Focus (AF): This feature automatically adjusts the lens to keep your subject in focus. Modern cameras come with advanced auto-focus systems that are fast and accurate. For quick and accurate auto-focus, the electronic components of your camera and your lens must work in tandem; therefore it’s important to carefully research both lenses and cameras if you’re hoping for top-notch autofocus.
Final Thoughts: The Importance of Choosing the Right Lens
Here are a few more (non-exhaustive) factors to consider when lens shopping:
Sensor Size: Different cameras have different sensor sizes (e.g., full-frame, APS-C, Micro Four Thirds). Ensure your lens is compatible with your camera’s sensor size to avoid issues like vignetting or cropping.
Portability: Traveling, hiking, adventuring? Consider a small, lightweight lens for comfort and convenience. Shooting weddings or sports? Use something a little beefier and more versatile (if you want).
Lens Diameter: Take a look at the lens in question. It should have this symbol (Ø) on it, accompanied by a number. For example:
Ø77
This number denotes the physical diameter of your lens (in this case, 77 millimetres). It’s important to be aware of your lens diameter because…
Accessories: Once you know your lens diameter, you can start looking at accessories such as filters (which can allow you to darken/brighten or tint your shots in real time) or step-up rings, which will readily screw into the threads in the front of your lens.
Lenses: Daunting, Yet Fun
Understanding the basics of video camera lenses and their terminology empowers you to make informed decisions that enhance your videography. If you can understand things like zoom, aperture, lens mounts, manual focus, and auto-focus, you can master them, thereby allowing you to select the best lenses for your needs and unlock the full potential of your camera.
If you’re looking for a lens expert to do some videography work for you, we’d love to help you out! Get in touch today - we’d be happy to hear from you to discuss your video project.
